I've had a new in box P2K E6 sitting for a long time. I got it out, ran it on DC, everything runs fine. It is a nice running loco. The mars light is cool!
I would like to use a 2 function decoder (DH126P), and use the yellow wire for the mars light, since there is no rear light, just a head light, and a mars light.
I found an article in the Digitrax help desk, it says to move the yellow wire to the unused pin on the harness, then change some CV's.
While I'm waiting for a response from Digitrax, I thought I'd throw it out here.
Anybody have any experience converting these locos to DCC ?
Thanks,
Mike.
My You Tube
Yes - it will work as shown in the Digitrax app note. However, most decoders can do a better Mars light simulation than the dual filament light bulb and all that circuitry on the factory board. So for ones I converted, I put LEDs in the front replacing the light bulbs and just hard wired the decoder. The only difference in the decoder settings is that in that app note they configure the yellow wire to jsut be on or off, since it is controllign the factory Mars circuit. For a direct wired, replaced with LEDs setup you would set the effect for the yellow wire to Mars, instead of simple on/off. Everything else would be the same.
Older Digitrax decoders didn't do LEDs very well for effects. The newer ones are supposed to be better. I don't know, early on I switched to TCS and used T1's in the E units.
Depending on just how long it's been sitting in the box, you might want to double check the stall current. There was a brief period when some got motors that draw as much as 4 amps. Run fine on DC, but will fry most decoders. Other than that particular batch, they are fine and should work with most any 1 amp or betetr decoder.
--Randy
Modeling the Reading Railroad in the 1950's
Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.
OK, stall current came to .76. I've changed the yellow wire as per the app note, checked continuity on my solder job, all is good, loco runs great, but no lights.
There really is no markings on the light board or the decoder plug, as far as orientation, and I'm assuming I have it plugged in right, as the loco runs.
I'm not sure how I would do the hardwire, as there are 3 wires associated with the mars light.
To hard wire it, you repalce the light bulb with an LED and a resistor, connected between the yellow and blue wire.
The orange wire should be pin 1 on the 8 pin connector. The pin you moved the yellow wire to is pin 3, normally a no connection which allows yooou to plug the connector in backwards and cause no problems other than the lights are backwards and the loco will run backwards.
If it's plugged in correctly, at least the headlight should work. If not, perhaps you messed up oon the CV changes. Try resetting the decoder, CV8=8. It should run on address 3, and the headlight should come on in forward when F0 is on. With default programming, that should make the mars light come on in reverse as long as F0 is on. If that works, then you cna try again to remap the yellow wire to make the mars light independent.
Thanks Randy, so far I have no lights, so in the morning, I'm going to switch the position of the plug, and put in the other way.
I'll probably just ending up hard wireing it, which is what the Digitrax support guy suggested.
It looks like the mars light, is a incandecent bulb that has two filaments, and flashes back and forth. I don't think I can do that with an LED.
If I have to forget the mars light, no big deal.
Now I have to start looking for the correct passenger cars for it. It's the black, with a yellow strip, Atlantic Coast Line.
You don't have to duplicate the dual filaments with an LED. The decoder itself can flash an LED and make it look like a Mars light. All that circuitry on the factory booard is for a circuit that alternated between lighting the two filaments. You don;t need any of that with a decoder, you need just an ordinary bulb or LED. If you look at the options for the functions in the decoder, you'll see one of the options is Mars light. There's also stuff like rotary beacon, double flash strobe, and random flicker. No external circuitry needed to get those effects, just the function wire connected to an LED, with the proper resistor.
This morning, just for S's & G's, I changed the position of the plug. I now have lights, and pressing F1 gives me the mars light, and in reverse, I have headlight and mars light.
What I thought was the obvious way that the plug went into the socket, was backwards. I hesitated to do this earlier, as I wasn't sure what might happen if I reversed the plug.
The next time I'am my LHS, I'll pick up a couple 6 function decoders, for experimenting with other light effects.
I learned that the economy 2 function DH126 only gives me head light and reverse light. I tried some flashing ditch lights on a P40, but that ain't happening with a 2 function. The green and purple function wires are not support by the economy 2 function DH126.
The Digitrax user group taught me that. You can tell how many functions a Digitrax decoder has by the second number.
Thanks Randy.
Yup, if you're using an eight-pin plug connection to the decoder and the lights don't come on when you hit the appropriate function button, try moving the engine forward. If it goes backwards, you put the decoder in the wrong way around.
p.s. Technically you have a 50-50 shot at putting it in the right way; in reality, the first try is usually the wrong way about 90% of the time!
I personally like the two filament Mars light as it gives a true side to side sweep, like the prototype. The Mars light function on most decoders just gives a flash and fade effect which does not look like the real thing. I have several Proto 2k E6 and 7s and I hard wired the decoder in, and kept the light board, and just sent the light output from the decoder to the original light board in the loco, which preserved the original Mars light feature. It looks cool at night with the headlight sweeping from side to side like the real thing.
It just occured to me that you could use the same Mars light board for the two filiment bulbs to operate ditch lights, but they would flash alternately constantly.
This past weekend I put a DH166PS into a P2K E7 with a mars light. To make it work, I simply soldered the green wire to the unused pin.
In decoder pro, I changed F0F to work in both directions, and turned off F0R. F1 worked by default to control the mars light.
I opted for a 6 function decoder over a 2 function decoder since they don't make anything in between (in the H series at least), and I wasn't sure if I wanted to replace the mars light with an LED or not.
After doing the install, I'm pretty confident a DH126 would have worked fine, following the articles directions. However, if I had to do it again, I think I would go with a DN136PS, since it has F1 but is a fair bit cheaper than the DH166PS.
As you probably read in my earlier post, I did move wire to the unused post, and I used the DH126.
My mistake was that I originally had the plug in backwards. When I turned it around, everything worked, mars light with F1.
Digitrax doesn't make a 4 func, so you have to go to the 6. I learned that lesson, in kind of a comical way, trying to get ditch lights on a P40 to flash.
EDIT: To clarify what I did, since the green and purple wire aren't supported by the 2 func. DH126, and there is no back light on the E6, I used the yellow wire (reverse light), soldered it to the unused plug.